Assertion failed in function addImmutablePass

I tried to use a Python package with PyCall running the command:
pyimport("bispy")
where bispy is a package that runs under the Python distribution linked in my ENV variable. I get the following error:

However, running pyimport with classical packages such as scipy or sympy works fine. I really don't understand the error message and hence have no clue on how to solve it...
Any help appreciated!
Thanks.